U.S. Geological Survey Collects Data, Evaluates Water Quality in Utah

Every five years, the United States Geological Survey compiles data detailing the amount of water consumed by agriculture, municipal and industrial uses, mining, private industrial wells and thermoelectric generation.

Prior to 1985, state comparisons are not possible because data were released by basin, explained the latest research report compiled by the Utah Foundation.

The latest U.S. Geological Survey data confirmed that Carbon County residents and Utahns at locations across the state consumed 4.76 billion gallons of water per day in 2000. Irrigation remained the largest water use category statewide.

In addition to the increase in the percentage of water used for irrigation purposes, the consumption of municipal water per capita in Utah climbed during the five-year period between 1995 and 2000, pointed out the foundation researchers.

In 1995, 269 gallons of water per person were consumed daily residents in the state.

In 2000, Utah's per capita water consumption jumped to 293 gallons, representing one of the largest increases reported in the country.

Only four states - Colorado, Hawaii, Texas and Louisiana - reported larger increases in per capita municipal water usage in 2000.

All four of the states were experiencing drought conditions in 2000 and mounting demand by residents for outdoor water may explain the increase in consumption.

Utah's per capita usage fluctuates significantly between drought and non-drought years, noted the foundation researchers.

In 1990, Utah's daily per capita water usage rate registered at 308 gallons. In 2000 during the latest drought cycle, the statewide rate dropped to 293 gallons per day.

Approximately 83 percent of the variance reported from 1985-2000 may be explained by the status of the statewide drought cycle, continued the independent public policy organization's researchers.

A climbing number of Utah's municipal and industrial water is coming from secondary systems, confirmed the foundation researchers. The approach has mixed results and may encourage residents to use more water outdoors than necessary since secondary systems charge less for water than culinary systems. The rate structures for secondary water are usually flat, creating no incentive to conserve.

Water is classified to have one of two sources of origin. Water comes from surface sources like lakes, rivers and streams or from ground sources like springs and wells.

In Utah, 78.6 percent of total water withdrawals are from surface sources. However, for public drinking water supplies, 57.1 percent comes from ground water sources. Ground water tends to be of a higher quality and requires less treatment to reach drinking or culinary quality, explained the foundation researchers. Utah's 57.1 percent ranks the state 10th in the nation for the percentage of public drinking that originates from ground sources.

By comparison, Colorado is one of the lowest ground water users in the nation. In Colorado, 6 percent of the state's publicly supplied drinking water originates from ground sources. Conversely, Idaho and New Mexico receive more than 88 percent of the states' drinking water from ground sources.

In New Mexico, there is little potable surface water to utilize in public systems. In Idaho, the situation appears to be a case of water rights. Most of the surface water in Idaho goes for irrigation and municipalities need to search elsewhere for resources.

An ongoing concern regarding ground water consumption centers around the fact that the supply is not as readily replenished and over-usage of the resource will dry up deep aquifers, noted the foundation researchers. In the Intermountain West and Utah, ground water usage has fluctuated, peaking in 1990.

The shift to a greater reliance on ground water can, in part, be attributed to concerns about surface source quality, pointed out the foundation researchers. The U.S. Environmental Protection Agency provides analysis of surface water quality for states. Assessments are performed on all types of surface water, including lakes, rivers, reservoirs, bays and estuaries along with near and off-shore oceanic water quality. Bay, estuary and ocean data were not analyzed by foundation researchers since the sources do not typically provide water for municipal systems.

Utah's water quality rates fairly well. Overall, Utah's water ranks eighth for river and seventh for lake/reservoir quality. The majority of the Intermountain states receive high ratings on at least one indicator. Colorado ranks second in the nation for river and lake quality. Montana is the overall lowest performing state, primarily due to surface water pollution from mining activities.

The overall good ratings of the Intermountain West are due in large part to geography and demographics. Many of the nation's rivers have a genesis in the Rocky Mountains and the low population density of the area means water exiting the Intermountain region are relatively clean, concluded the Utah Foundation researchers.